Landman comes back and says," oops I made a mistake 20 months ago so send me the money back! its spent and gone! now what? Thanks for answers

Dear Mr. Williams,

On a mutual mistake situation, would not the bonus dollars be returned? Here is my language to avoid the Lessee dancing on the head of a pin with a seizure claim after a broad disclaimer of warranty:

“It shall be the responsibility of Lessee to make title examinations sufficient to satisfy itself as to Lessor’s right, title and interest in the Leased Premises and the rights of Lessor to execute this Lease.”